Hybrid systems and methods for managing thermal energy

ABSTRACT

In one aspect, thermal energy storage systems are described herein. In some embodiments, such a system includes at least one active thermal storage battery and at least one passive thermal storage battery. The at least one active thermal storage battery includes a container, a heat exchanger disposed within the container, and a first phase change material disposed within the container and in thermal contact with the heat exchanger. The at least one passive thermal storage battery comprises a plurality of thermal storage cells, individual thermal storage cells comprising a container having an interior volume, and a second phase change material disposed within the interior volume of the container.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority pursuant to 35 U.S.C. § 119 to U.S.Provisional Patent Application Ser. No. 63/108,523, entitled “HYBRIDSYSTEMS AND METHODS FOR MANAGING THERMAL ENERGY,” filed on Nov. 2, 2020,which is hereby incorporated by reference in its entirety.

FIELD

The present disclosure relates to thermal energy storage and managementsystems including a phase change material (PCM) or latent heat storagematerial, and to methods of storing and releasing thermal energy usingsuch systems.

BACKGROUND

The production of electricity is generally more expensive during peakdemand hours than at low demand hours. Therefore, various thermal energystorage systems have been developed which permit the storage of thermalenergy for later use, such as during peak demand hours. Such deferreduse of stored energy can reduce strain on the power grid and/or reducethe average cost of energy per kilowatt-hour during peak load periods.However, some previous thermal energy storage systems suffer from one ormore disadvantages, such as short thermal energy storage periods, lowefficiency, low versatility, and difficulty of installation.

Additionally, when temperatures in a climate-controlled environment passcertain thresholds, as may occur in the event of a power outage or inextreme external temperatures, additional or supplemental thermal energycontrols may be desired. However, some previous thermal energy storagesystems may be limited to exclusively passive thermal energy controlmeasures or active thermal energy control measures tied to a singletemperature control point. Improved thermal energy storage systems aretherefore desired.

SUMMARY

In one aspect, thermal energy storage and management systems aredescribed herein. Such systems, in some cases, can provide one or moreadvantages compared to some existing systems. In some embodiments, forexample, a system described herein can provide more versatile thermalenergy storage and release than some existing systems. A systemdescribed herein, in some cases, can be used to actively buffer orrecover a desired environmental or room temperature. Additionally, asystem described herein can be used to passively buffer a desiredenvironmental or room temperature. Moreover, a system described hereincan actively buffer or recover a first desired temperature whilepassively buffering a second temperature.

In some embodiments, a thermal energy management system described hereincomprises at least one active thermal storage battery and at least onepassive thermal storage battery. The at least one active thermal storagebattery comprises a container, a heat exchanger disposed within thecontainer, and a first phase change material disposed within thecontainer and in thermal contact with the heat exchanger. The at leastone passive thermal storage battery comprises a plurality of thermalstorage cells. Individual thermal storage cells comprise a containerhaving an interior volume and a second phase change material disposedwithin the interior volume of the container. In some such systemsdescribed herein, the active thermal storage battery may have a chargingstate and/or a discharging state. While in the charging state, theactive thermal storage battery maintains the first phase change materialin a first phase or returns the first phase change material to the firstphase. While in the discharging state, the active thermal storagebattery transfers thermal energy from an environment or room external tothe first phase change material to the first phase change material bychanging the first phase change material to a second phase from thefirst phase.

As described further herein, it is also to be understood that variouspowered components can be connected to a thermal energy managementsystem of the present disclosure to provide certain desirablefunctionality in a given configuration. For example, a chiller isattached to or associated with the active thermal storage battery toenable the first phase change material to be maintained in or returnedto the first phase. Such systems may comprise one or more fans for airhandling and exchange to facilitate air flow of temperature managed airand to ensure thermal communication between the active thermal storagebattery and the environment or room. In certain cases, systems describedherein comprise an electrical switch and/or a thermostat which may beused to initiate a charging state and/or a discharging state. Systemsdescribed herein may comprise a fluid pump operable to flow fluidthrough the heat exchanger in the active thermal storage battery. Thepowered component(s) may be powered by a traditional power grid, one ormore batteries, or a hybrid system in which one or both of the powergrid and the battery or batteries power the powered component(s)concurrently or sequentially, as in the case of a battery backup system.

In another aspect, methods of managing the temperature of a room aredescribed herein. In some cases, such a method comprises disposing oneor more thermal energy management systems described herein in thermalcommunication with the room. In such embodiments, the environmentexternal to the phase change material is an interior of the room. Suchmethods may further comprise initiating the discharging state tomaintain a temperature of the room or to reduce a temperature of theroom by changing the first phase change material from the first phase tothe second phase. Additionally, in some cases, methods described hereinmay comprise initiating the charging state to maintain the first phasechange material in the first phase or to revert the phase changematerial from the second phase to the first phase. In certain cases,initiating the discharging state or the charging state may be performedin part or in whole by a thermostat or other electric switch.

These and other implementations are described in more detail in thedetailed description which follows.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates a perspective view of an example of an internal viewof a room of a thermal energy storage and management system.

FIG. 1B illustrates a perspective view of an example of an external viewof an environmental enclosure with a thermal energy storage andmanagement system.

FIG. 2A illustrates a perspective view of an example of a module thermalenergy storage and management system.

FIG. 2B illustrates an additional perspective view of an example of amodule thermal energy storage and management system.

FIG. 3A illustrates a perspective view of an example embodiment of apassive thermal storage battery.

FIG. 3B illustrates a top view of a room or environmental with anexample of a thermal energy storage and management system.

FIG. 4A illustrates a perspective view of an additional example of anexternal view of an environmental enclosure with a thermal energystorage and management system.

FIG. 4B illustrates a perspective view of an additional example of athermal energy storage and management system.

FIG. 4C illustrates a perspective view of an additional example of athermal energy storage and management system.

FIG. 4D illustrates the structure of an example embodiment of a passivethermal storage battery.

FIG. 5A illustrates an example of a layout or room for use with athermal energy storage and management system.

FIG. 5B illustrates a top down view of a layout or room for use with athermal energy storage and management system.

DETAILED DESCRIPTION

Implementations and embodiments described herein can be understood morereadily by reference to the following detailed description, examples,and drawings. Elements, apparatus, and methods described herein,however, are not limited to the specific implementations presented inthe detailed description, examples, and drawings. It should berecognized that these implementations are merely illustrative of theprinciples of the present disclosure. Numerous modifications andadaptations will be readily apparent to those of skill in the artwithout departing from the spirit and scope of the disclosure.

In addition, all ranges disclosed herein are to be understood toencompass any and all subranges subsumed therein. For example, a statedrange of “1.0 to 10.0” should be considered to include any and allsubranges beginning with a minimum of 1.0 or more and ending with amaximum value of 10.0 or less, e.g., 1.0 to 5.3, or 4.7 to 10.0, or 3.6to 7.9. Similarly, as will be clearly understood, a stated range of “1to 10” should be considered to include any and all subranges beginningwith a minimum of 1 or more and ending with a maximum value of 10 orless, e.g., 1 to 6, or 7 to 10, or 3.6 to 7.9.

All ranges disclosed herein are also to be considered to include the endpoints of the range, unless expressly stated otherwise. For example, arange of “between 5 and 10,” “from 5 to 10,” or “5-10” should generallybe considered to include the end points of 5 and 10.

FIGS. 1-5B illustrate one or more non-limiting, exemplaryimplementations and embodiments of thermal energy storage systems and/orthermal energy management systems described herein. While it is to beunderstood that the components or features depicted in theaforementioned figures are merely representative of one implementationof these components or features, the reference numerals used in thesefigures correspond with the following nomenclature for such componentsor features in the implementations shown in the figures:

-   100 Thermal Energy Storage and Management System-   102 External View of a Room and/or Environmental Enclosure-   104 Internal View of a Room and/or Environmental Enclosure-   106, 206, 406 Fan Coil-   108, 208, 408 Chiller-   110, 210, 310, 410 Passive Thermal Storage Battery-   112, 212, 412 Active Thermal Storage Battery

I. Thermal Energy Storage and Management Systems

Systems described herein may be used for a variety of end-uses orapplications, including, but not limited to thermal energy storage,release, cooling, and management for industrial, commercial, and/orresidential buildings. Such applications may be desired, such asso-called load shifting of energy use of a heating, ventilating, and airconditioning (HVAC) system of a building, or for load shifting of otherenergy used by the building. In this manner, as described above, thecost of energy obtained from a power grid or from an alternative sourceof energy (such as a solar panel) can be reduced. Alternatively, oradditionally, such applications may be desired to provide emergency orback-up heating or cooling for an environment for a limited time tosupplement or temporarily replace the HVAC system of a building.Further, systems described herein can be used to reduce energyconsumption of a cooling or climate-control mechanism when sensitivityto overall power draw or total energy used over a given time period in aroom or environment is desired. For example, during a power outage,systems described herein can actively and/or passively buffer roomtemperature while minimizing total energy draw from one or more backupenergy systems, such as a battery bank. Additionally, or alternatively,systems described herein can be used as a fail-safe or backup system inthe event an HVAC system fails to operate normally, providing a periodof time for an HVAC technician or repair team to arrive whilemaintaining a desired operational temperature or range within the roomor environment. Thermal energy storage and management systems describedherein may be used advantageously for other purposes also, as describedfurther herein.

Referring now to FIG. 1A-B. In FIG. 1A, an illustration of a perspectiveview of an example of an internal view of a room 104 of a thermal energystorage and management system. In FIG. 1B, an illustration of aperspective view of an example of an external view of an environmentalenclosure or room with a thermal energy storage and management system.In one aspect, thermal energy storage and/or management systems aredescribed herein. Thermal energy management systems 100 described hereincomprise at least one active thermal storage battery 112 and at leastone passive thermal storage battery 110. As referenced herein, an“active” thermal storage battery 112 may have multiple modes ofoperation (such as a charging state and a discharging state) such that atemperature of a room or environment may be actively managed during aspecific time period, as during a discharging state, and may not bemanaged by the active thermal storage battery 112 during other times, asduring a charging state. An active thermal storage battery 112 maycomprise or include additional features or components which may or maynot be powered in order to further facilitate this functionality. Forexample, an active thermal storage battery 112 may comprise or includeone or more heat exchangers and optionally one or more poweredcomponents. Any such components or features may be included consistentwith the present disclosure. Certain non-limiting examples may include afan coil 106, chiller unit 108, thermostat, electrical switch, and/or afluid pump.

A “passive” thermal storage battery 110, as referenced herein, comprisesa container having an interior volume and a phase change materialdisposed within the interior volume of the container, but may notinclude a heat exchanger to facilitate thermal energy transfer betweenthe PCM and the environment. While a passive thermal storage battery 110may comprise or include a fan or similar air flow management systems,such systems (not intending to be bound by theory) may provide thermalmass and/or thermal storage based solely or primarily on a phasetransition temperature tied to a desired temperature or range oftemperatures, rather than with the use of one or more powered componentsto charge/discharge the system as needed. Not intending to be bound bytheory, passive thermal storage batteries 110 may rely on air flow orin-room contact with the ambient air of the room or environment tocondition or otherwise thermally manage the room or environment. Passiveflow of air, utilizing a passive thermal storage battery, is disclosedfurther in additional embodiments of FIGS. 5A-B.

Active thermal storage batteries 112 of systems described hereincomprise a container. Any container not inconsistent with the objectivesof the present disclosure may be used. Moreover, the container can haveany size, shape, and dimensions and be formed from any material orcombination of materials not inconsistent with the objectives of thepresent disclosure. The container is selected based upon system needs,and the dimensions are reflected based on the usage area, the amount ofthermal regulation, and the goals of the room or environmentalenclosure. In some embodiments, for example, the container is made fromone or more weather-resistant materials, such as a polymer or syntheticrubber, thereby permitting installation of the system in an outdoorenvironment. In some cases, the container is metal or formed from ametal or a mixture or alloy of metals, such as aluminum. In otherinstances, the container is formed from plastic or a composite material,such as a composite fiber or fiberglass material.

Additionally, in some instances, the container of an active thermalstorage battery 112 described herein, provides functionality beyondcontainment of the PCM and heat exchanger. For example, in some cases, acontainer comprises exterior walls, interior walls, and a thermallyinsulating material disposed in between the exterior walls and theinterior walls. Any thermally insulating material not inconsistent withthe objectives of the present disclosure may be used. In someembodiments, the thermally insulating material is air or a vacuum. Inother cases, the thermally insulating material comprises a foam, such asa polyisocyanurate foam. Further, in some instances, the exterior wallsand/or the interior walls of the container are formed from a metal,plastic, composite material, or a combination of two or more of theforegoing. It is further to be understood that such exterior andinterior walls (as well as anything disposed between them, such as athermally insulating material) can together form each “side wall” and“floor” of the container. Similarly, in some instances, a cover of acontainer described herein likewise comprises exterior walls, interiorwalls, and a thermally insulating material disposed in between theexterior walls and interior walls. Further, in some implementations, the“cover” is formed from such a “multi-layered” or composite cover, thoughthe individual layers (e.g., the thermally insulating material disposedwithin the cover) are not expressly shown in the figures.

Moreover, in some embodiments described herein, the floor, side walls,and/or cover of the container have an R-value of at least 4square-foot*degree Fahrenheit*hour per British thermal unit per inch(ft2*° F.*h/BTU*inch). In some cases, the floor, side walls, and/orcover of the container have an R-value of at least 5, at least 6, or atleast 8 (ft2*° F.*h/BTU*inch). In some instances, the R-value of thefloor, side walls, and/or cover is between 4 and 10, between 4 and 8,between 4 and 6, between 5 and 10, between 5 and 8, or between 6 and 10(ft2*° F.*h/BTU*inch).

Additionally, in some cases, a gasket, seal, or sealing layer isdisposed between the cover and the side walls of a container describedherein, or is disposed within or forms part of the cover. Such a gasketmay be part of the main body of the container, or part of the cover ofthe container. Further, such a gasket can provide further thermalinsulation and/or protection of the interior volume of the containerfrom external factors such as water or other materials that may bepresent in the exterior environment of the container/system,particularly when the container/system is disposed or installedoutdoors. The container of a system described herein may also include orcomprise lugs or other features on one or more exterior surfaces of thecontainer, such as one or more detachable lifting lugs disposed on oneor more exterior surfaces of the container.

Referring now to FIG. 2A, an illustration of a perspective view of anexample of a module thermal energy storage and management system. FIG.2B, an illustration of an additional perspective view of an example of amodule thermal energy storage and management system. In some preferredembodiments, it is particularly to be noted that the container of theactive thermal storage battery 212 is not a standard shipping container.For example, in some embodiments, the container is not a containerspecifically approved by the Department of Transportation for shipping,such as a container having exterior dimensions of 20 feet by 8 feet by 8feet. A container for use in an active thermal storage battery describedherein, in some embodiments, can have other dimensions. The size andshape of the container, in some embodiments, are selected based on oneor more of a desired thermal energy storage capacity of the system, adesired footprint of the system, and a desired stackability orportability of the system. For example, although the container is notitself a standard shipping container, it is to be understood that acontainer of a thermal energy management system described herein can befitted or placed inside of a standard shipping container, such as forease of shipment or transport of the system. In some preferredembodiments, the container of a thermal energy management systemdescribed herein has overall length, width, and height dimensions thatpermit two containers of two separate systems to be stacked on top ofanother (two high) and then placed within a standard shipping container.Further, in some cases, the overall dimensions of each container of eachseparate system are selected to permit an integral number (e.g., 4, 5,or 6) of “two-high” stacks to be placed or fitted within the interior ofa standard shipping container. However, the exterior dimensions of thecontainer of an active thermal storage battery described herein are notparticularly limited, and other dimensions may also be used.

Active thermal storage batteries 212 described herein, further compriseat least one heat exchanger disposed within the container. Any heatexchanger may be used consistent with the objectives of the presentdisclosure. A heat exchanger described herein can, in some embodiments,comprise or include an inlet pipe or header, an outlet pipe or header,and a number n of thermal transfer or heat exchange plates in fluidcommunication with the inlet pipe and the outlet pipe such that a fluidflowing from the inlet pipe and to the outlet pipe flows through theplates in between the inlet pipe and the outlet pipe, wherein the firstPCM is in thermal contact with the plates, and wherein the number n isat least 2. In some cases, the number n is at least 5, at least 10, atleast 20, or at least 50. In some instance, the number n is between 2and 500, between 2 and 250, between 2 and 100, between 5 and 500,between 5 and 100, between 10 and 200, between 10 and 100, between 10and 40, between 20 and 200, or between 20 and 100. However, the numberof plates is not particularly limited and can be chosen based on theoverall dimensions of the container, the spacing between plates, theamount of PCM, and/or the desired latent heat capacity of the system.Moreover, as described above, it is to be understood that fluidgenerally enters the heat exchanger apparatus through a “proximal” endof the inlet pipe and generally exits the heat exchange apparatusthrough a “distal” end of the outlet pipe or (in some cases) through adistal end of the inlet pipe. Additionally, in some instances, a fluidflowing into the inlet pipe and out of the outlet pipe flows through atleast a portion of the plates or through some of the plates afterflowing into the inlet pipe but before flowing out of the outlet pipe.

Turning now to the relationship between the container of a systemdescribed herein and the heat exchanger disposed within the container,it is to be understood that the heat exchanger or heat exchangeapparatus can be disposed, installed, or fitted within the container(e.g., within or primarily within the interior volume of the container)in any manner not inconsistent with the objectives of the presentdisclosure. For example, in some cases, the entire volume or almost theentire volume of the heat exchanger is disposed within the interiorspace of the container, and only a small portion or only one or moreconnector portions of the heat exchanger are disposed or configuredoutside the container for purposes of providing access to the plates orother majority portion of the heat exchanger inside the container. Insome embodiments, for instance, the inlet pipe of the heat exchanger (ora connector portion thereof) passes through (or partially through) anexterior wall of the container, thereby providing fluid communicationbetween the plates and an exterior of the container. Similarly, in somecases, the outlet pipe (or a connector portion thereof) of the heatexchanger passes through (or partially through) an exterior wall of thecontainer, thereby providing fluid communication between the plates andan exterior of the container.

As described further herein, it is to be understood that variousexterior systems can be connected to the thermal energy managementsystem, such that fluid communication is provided between the plates ofthe thermal energy management system and the exterior systems. Forinstance, in some cases, at least one powered component such as an HVACchiller, fluid pump, thermostat, electrical switch, and/or fan coil.

Powered components of active thermal storage batteries described hereinmay comprise or include a chiller, such as an HVAC chiller. The chillerunit may be operable to maintain the first PCM in a first phase or toreturn the first PCM to the first phase during a charging state. Thechiller may be in fluid communication with the fluid in the heatexchanger to cool the fluid in order to remove thermal energy from thefirst PCM or, if operated in the reverse configuration, to heat thefirst PCM. The fluid can be any fluid not inconsistent with theobjectives of the present disclosure. In some implementations, forinstance, the fluid comprises a thermal fluid. For reference purposesherein, a thermal fluid can be a fluid having a high heat capacity. Insome cases, a thermal fluid also exhibits high thermal conductivity.Moreover, the external fluid can be a liquid or a gas. A liquid fluid,in some embodiments, comprises a glycol, such as ethylene glycol,propylene glycol, and/or polyalkylene glycol. In some instances, aliquid fluid comprises liquid water or consists essentially of liquidwater. A gaseous fluid, in some embodiments, comprises steam. The activethermal storage battery may additionally and/or alternatively compriseor include a fluid pump. The fluid pump may be operable to flow fluidthrough the heat exchanger in the thermal storage battery. In addition,the fluid pump may be operable to flow fluid through or past a fan coilto permit air from the room or environment to be heated or cooled and tothen be redistributed to the room or environment.

An active thermal storage battery described herein may have or beadapted or configured to operate in a charging state and/or adischarging state. While in the “charging” state, the active thermalstorage battery maintains the first PCM in a first phase or returns thefirst PCM to the first phase. For example, a first phase of the PCM maybe solid, and it may be desired that the PCM is held or “charged” in thesolid state until demand occurs for thermal energy transfer to storethermal energy in the PCM. Such an arrangement may be preferred wherethe expected demand is thermal energy storage in the PCM to cool theenvironment. In certain other applications, the reverse may be true,where the first PCM may be held in a first phase which is liquid, andmay be held or returned to this state until there is demand for thermalenergy transfer from the PCM to solidify the PCM. Such an arrangementmay be desired where the anticipated need is to release thermal energyfrom the PCM to heat the room or environment. Either direction of energytransfer may be desired, whether the anticipated need is thermal energystorage in the PCM or release of thermal energy from the PCM.

Consistent with the above discussion of the “charging” state, while inthe “discharging” state, the active thermal storage battery may transferthermal energy from the environment external to the first PCM to thefirst PCM by changing the first PCM from the first phase to a secondphase to cool the environment. In other applications, the dischargingstate may transfer thermal energy from the PCM to the environment bychanging the PCM from the first phase to the second phase to heat theenvironment. An active thermal storage battery of systems describedherein may have both the charging state and the discharging state, andmay be operable to switch between the two.

In order to initiate the charging state and/or the discharging state,one or more controls may be included in the system. For example,initiating the discharging state may be achieved by a thermostat whichdetects that a setpoint has been met or exceeded (or, in the even thatthe thermal storage battery is heating the environment, that thetemperature is at or below the setpoint). Additionally or alternatively,an electrical switch may be operable to permit manual input by a user todetermine if the charging state or discharging state should beinitiated.

Moreover, in some instances, an electrical switch may be configured todetect a power outage or a change in power source in order to initiatethe charging state or the discharging state. In such embodiments, afirst power source for one or more of the powered components of thesystem may be a traditional power grid. As referenced herein, a“traditional power grid” refers to a centralized generation ofelectricity which may or may not be located in the same geographic areaas the load being served. In these instances, the electrical switch maybe operable to detect the loss of power provided by the traditionalpower grid, and to initiate the discharging state to thermally managethe room or environment in thermal communication with the thermalstorage battery. Additionally, or alternatively, a source of power maycomprise at least one battery or a plurality of batteries. The source ofpower may be a lone or sole source, a primary source or a backup sourceof power, or may power some components while the traditional power gridpowers other components. In certain implementations, the electricalswitch may detect that a source or primary source of power changes fromthe traditional power grid to the battery or batteries (or vice versa),and may initiate the charging state or discharging state, as required.

The condition for initiating the charging state or discharging state maybe tied to operational conditions of the room or environment beingmanaged by the thermal energy management system. For example, the roomor environment may have an operational minimum temperature and/or anoperational maximum temperature. These temperatures maybe tied to thecomfort of one or more occupants of the room or environment.Alternatively, or additionally, these temperatures may be dictated byoperating or performance benchmarks of electrical or electronicequipment disposed in the room or environment. For example, anoperational minimum temperature may be dictated by or tied to anexpected or calculated battery capacity of one or more batteriesdisposed in the room or environment within a given temperature range.For example, a battery that provides 100 percent capacity at 27° C. maydeliver only 50 percent of this capacity at 0° C., thus it may bedesirable that a temperature is selected as an operational minimumtemperature between these two values, such as between about 15° C. and25° C. More specifically, an operational minimum temperature may be ator about 20° C. in such cases. Likewise, an operational maximumtemperature may be selected to maximize capacity while controllingbattery discharge rate. In such instances, an operational maximumtemperature may be between 20° C. and 35° C., such as between about 25°C. and 35° C., or between about 25° C. and 30° C., and may morespecifically be about 27° C.

In some embodiments, the first setpoint temperature may be greater thanor equal to the operational maximum temperature, and may be higher thana phase transition temperature of the first phase change material fromthe first phase to the second phase. In some such embodiments, the firstsetpoint temperature is between 5° C. and 50° C. higher than the phasetransition temperature of the first phase change material from the firstphase to the second phase, such as between 5° C. and 45° C. higher,between 5° C. and 40° C. higher, between 5° C. and 35° C. higher,between 5° C. and 30° C. higher, between 10° C. and 40° C. higher,between 15° C. and 40° C. higher, between 20° C. and 40° C. higher, orbetween 10° C. and 30° C. higher, such as between 20° C. and 30° C.higher than the phase transition temperature. Alternatively, the firstsetpoint temperature can be lower than the phase transition temperatureof the first setpoint temperature. In some such embodiments, the firstsetpoint temperature is between 5° C. and 50° C. lower than the phasetransition temperature of the first phase change material from the firstphase to the second phase, such as between 5° C. and 45° C. lower,between 5° C. and 40° C. lower, between 5° C. and 35° C. lower, between5° C. and 30° C. lower, between 10° C. and 40° C. lower, between 15° C.and 40° C. lower, between 20° C. and 40° C. lower, or between 10° C. and30° C. lower, such as between 20° C. and 30° C. lower than the phasetransition temperature of the first PCM.

In certain embodiments of systems described herein, it may be desiredthat an overall power draw of the one or more powered components is lessthan a total latent heat of the first PCM, in particular over anoperational time frame of the discharging state. Reduced power draw orpower utilization during the discharging state relative to a traditionalHVAC system, for example, may be desired where the thermal energymanagement systems described herein are being operated primarily orentirely by one or more batteries. In such embodiments, this reducedpower draw may permit the battery or batteries to more effectively powerother components external to the thermal energy management system.Additionally and/or alternatively, such an arrangement may permit alonger cycle time of the discharging state or more cycles between thecharging state and discharging state. For example, in some embodiments,the power draw of the one or more powered components, in total, may beless than a latent heat of the first PCM over a period of up to 8 hours,such as over a period of 1-4 hours, 1-5 hours, 1-6 hours, 2-5 hours, or3-5 hours. For instance, in some embodiments, a total power draw of thepowered component(s) may be less than a latent heat of the first PCMover a period of 1 hour, 2 hours, 3 hours, 4 hours, or 5 hours.

Referring now to FIG. 3A-B. FIG. 3A illustrates a perspective view of anexample embodiment of a passive thermal storage battery. FIG. 3Billustrates a top view of a room or environmental with an example of athermal energy storage and management system. Thermal energy managementsystems described herein further comprise at least one passive thermalstorage battery 310. Passive thermal storage batteries 310 of systemsdescribed herein comprise a plurality of thermal storage cells (See FIG.4D), with individual thermal storage cells comprising or including acontainer having an interior volume and a second phase change materialdisposed within the interior volume of the container. Containers ofthermal storage cells described herein comprise an exterior surfacedefining an interior or internal volume. A container used in a thermalstorage cell of a passive thermal storage battery described herein canhave any shape or arrangement consistent with the present disclosure.For example, in some embodiments, the container has the form or shape ofa plate, blade, grid, or panel. The plate, blade, grate, grid, or panel(referred to collectively as a “container” below, for convenience) canbe generally square or rectangular in cross section (e.g., such that thecontainer is a relatively short or “flat” rectangular cylinder).Additionally, the container may include a fill spout. The fill spout(when in in an open configuration, as opposed to a closed or sealedconfiguration) provides fluid communication between the interior volumeand the external environment of the container. The exterior surface ofthe container includes a front side, a back side, and at least fourcorners. The fill spout is disposed at one of the corners of theexterior surface.

Further, in some preferred embodiments, a container of a thermal storagecell of a passive thermal storage battery 310 described herein alsocomprises a cap. More particularly, such a cap can cover, enclose, or“complete” the corner where the fill spout is disposed. Thus, in somecases, for instance, surfaces of the cap align with the exterior surfaceof the container to conceal the corner fill spout.

For example, in some embodiments, the container can be generally squareor rectangular in cross section (e.g., such that the container is arelatively short or “flat” rectangular cylinder). Moreover, in certainpreferred embodiments, the container has a relatively high surface areato volume ratio. For example, in some cases, the container can have asurface area to volume ratio (e.g., in units of cm²/cm³) of at least1:2, at least 1:3, at least 1:4, at least 1:5, at least 1:10, at least1:20, at least 1:50, or at least 1:100. In some embodiments, thecontainer has a surface area to volume ratio between about 1:3 and1:100, between about 1:3 and 1:50, between about 1:5 and 1:100, betweenabout 1:5 and 1:50, or between about 1:10 and about 1:100. Similarly, insome cases, the average thickness of the container can be relativelysmall compared to the average length and average width of the container.For instance, in some embodiments, the average length and the averagewidth of the container are at least 5 times, at least 10 times, at least20 times, or at least 50 times the average thickness of the container.In some cases, the average length and the average width of the containerare 5-100, 5-50, 5-20, 10-100, or 10-50 times the average thickness ofthe container.

Moreover, in some preferred implementations, the exterior surface of thecontainer further comprises one or more protrusions. The protrusionsextend in an orthogonal or substantially orthogonal (e.g., within 15degrees, within 10 degrees, or within 5 degrees of orthogonal) directionfrom the back side of the container. As further described herein, insome cases, the one or more protrusions are configured or operable toform a gap between the back side of the container and an adjacentsurface, such as a wall against which the container is disposed oranother container with which the container is stacked. The protrusionscan thus act as a spacer.

In addition, in some especially preferred embodiments, the exteriorsurface of the container further comprises one or more channelsextending from the front side to the back side and connecting the frontside to the back side. These channels may also be described as throughholes or perforations of the container.

In some cases, at least 90% of the interior volume of a container isoccupied by the PCM (which may be referred to below as a “thermalmanagement material”). In other cases, at least 95%, at least 96%, atleast 97%, at least 98%, or at least 99% of the interior volume isoccupied by the thermal management material. In other embodiments, thethermal management material occupies 50-100%, 60-100%, 70-100%, 80-100%,90-100%, 90-99%, 90-98%, 95-100%, or 95-98% of the interior volume ofthe container.

The exterior surface of container of a thermal storage cell of a passivethermal storage battery 310, in some embodiments, is operable tofacilitate heat transfer between an external environment and theinterior volume, or between the external environment and a PCM disposedwithin the interior volume. For example, in some embodiments, theexterior surface can comprise or be formed from one or more materialsthat facilitate heat transfer, such as a thermal exchange material or athermally conductive material. Any material operable to permit thermalexchange from the container to the external environment can be used.Thermally conductive materials which may form one or more materials ofthe container described herein have a thermal conductivity greater thanor equal to a thermal conductivity of the PCM disposed within theinterior volume of the container(s). Specifically, in some embodiments,the thermally conductive material has a thermal conductivity higher thana thermal conductivity of the PCM within the interior volume of thecontainer. Thermally conductive materials which may form one or morematerials of the container described herein may have a thermalconductivity of at least 0.2 W/m*K. For example, in some embodiments,thermally conductive materials have a thermal conductivity of at least0.4 W/m*K, such as at least 0.5 W/m*K, at least 0.75 W/m*K, or at leastW/m*K. In some instances, a thermally conductive material has a thermalconductivity of between 0.2 and 450 W/m*K, such as between 0.4 W/m*K and450 W/m*K, 0.2 and 400 W/m*K, 0.2 and 350 W/m*K, 0.2 and 300 W/m*K, 0.2and 250 W/m*K, 0.2 and 200 W/m*K, 0.2 and 150 W/m*K, or 0.2 and 100W/m*K. In some instances, the thermally conductive material has athermal conductivity of between 0.2 and 90 W/m*K, 0.2 and 75 W/m*K, 0.2and 50 W/m*K, and 0.2 and 25 W/m*K. In certain other implementations,the thermally conductive material has a thermal conductivity of between0.4 and 400 W/m*K, 0.4 and 350 W/m*K, 0.4 and 300 W/m*K, 0.4 and 250W/m*K, 0.4 and 200 W/m*K, 0.4 and 150 W/m*K, or 0.4 and 100 W/m*K. Inyet further embodiments, the thermally conductive material has a thermalconductivity of between 0.4 and 90 W/m*K, 0.4 and 75 W/m*K, 0.4 and 50W/m*K, and 0.4 and 25 W/m*K. In still further embodiments, the thermallyconductive material has a thermal conductivity of at least 7 W/m*K, suchas between 7 and 450 W/m*K. Additionally, in some instances, a thermalconductivity of the container is at least one order of magnitude higherthan a thermal conductivity of the PCM, such as at least two orders ofmagnitude higher, or at least three orders of magnitude higher. Notintending to be bound by theory, a container being formed from one ormore materials which has a thermal conductivity one or more orders ofmagnitude higher than the PCM within the container may facilitate heatabsorption and/or dissipation, thereby reducing “charging” time of thethermal storage cell and increasing the buffer time of the thermalstorage battery while being “discharged.”

Some non-limiting examples of materials usable for containers of thermalstorage cells of passive thermal storage batteries described hereininclude a polymeric or plastic material (such as a polyethylene,polypropylene, polyethylene terephthalate, polyvinyl chloride,polycarbonate, polyoxymethylene, acrylonitrile butadiene styrene, orpolyether ether ketone), a metal or mixture or alloy of metals (such asaluminum), and a composite material (such as a composite fiber orfiberglass). It is to be understood that the material forming or used toform the exterior surface of the container, in some preferredembodiments, can generally form or define the entire body of thecontainer or substantially the entire body of the container.Additionally, the material used to form the exterior surface (or theentire body or substantially the entire body of the container) can benon-breathable or non-permeable to water, and/or non-flammable orfire-resistant. Moreover, in some instances, the material used to formthe exterior surface (or the entire body or substantially the entirebody of the container) is non-electrically conductive, or has low orminimal electrical conductivity, such that the material is considered anelectrical insulator rather than an electrical conductor. The use of anon-electrically conductive material to form the exterior surface of acontainer described herein may be especially desirable, for example, ifthe container is placed in a room or space in which sensitive and/orexpensive electronic devices are used, such as a telecommunications dataroom or data center in which computer systems and associated componentsare housed.

Further, in some cases, a thermally conductive material described abovecan be dispersed within a non-thermally conductive material or within aless thermally conductive material. In some embodiments, for example, athermally conductive material comprises a paint, ink, or pigment, or ametal dispersed in a paint, ink, or pigment. Moreover, the paint, ink,or pigment can be used to form a design or decorative feature on theexterior surface of the container.

Additionally, the material forming the exterior surface (or the entirebody or substantially the entire body of the container) can have anythickness not inconsistent with the objectives of the presentdisclosure. In some embodiments, the thickness is selected based on adesired mechanical strength and/or thermal conductivity. For example, insome cases, the average thickness of the material forming the exteriorsurface (or the entire body or substantially the entire body of thecontainer) is less than 10 mm, less than 5 mm, less than 3 mm, or lessthan 1 mm. In some embodiments, the average thickness is between 1 and10 mm, between 1 and 5 mm, between 1 and 3 mm, between 3 mm and 10 mm,between 3 mm and 5 mm, or between 5 mm and 10 mm.

Moreover, in some embodiments, the exterior surface of the container canhave one or more features, such as edges that are flat, rounded,bullnose, or beveled connecting the front and back sides of the exteriorsurface. Other features of a container can include one or more recessedregions, protrusions, and/or channels. In some cases, one or morefeatures present on the front side of the container are also present onthe back side of the container. In other instances, the front side caninclude one or more features absent from the back side of the container,or vice versa.

In some embodiments, the exterior surface can further comprise one ormore channels, through-holes, or perforations. As described above, oneor more channels present in a container can increase the surface area ofthe container or air flow “through” the container (from the front sideto the back side). The presence, number, and size of channels can alsobe selected based on a desired thermal storage capacity of the container(e.g., as determined by a volume or mass of PCM disposed within theinterior volume of the container, where a larger total channel volumecorresponds to a smaller total volume of PCM, for a given sizecontainer). The channels can have any shape not inconsistent with theobjectives of the present disclosure. For example, in some cases, achannel has a shape (e.g., a sectional shape when viewed from the frontor the back side of the container) that is generally circular, oval, oroblong. The shape can also be a polygonal shape having sharp or roundedcorners. Further, in some embodiments, the channels (or the “sidewalls”of the channels) can have straight, rounded, beveled, or bullnose edgesconnecting the front and back sides of the exterior surface.

Additionally, in some example embodiments, a container described hereinfurther comprises a fill spout having an opening in fluid communicationwith the interior volume of the container and an external environment ofthe container. In some cases, the fill spout is generally cylindrical inshape. However, other shapes may also be used. The fill spout, in someembodiments, is disposed at one of the corners of the exterior surface.In some embodiments, the fill spout further comprises an air outlet. Theair outlet is operable to allow displaced air to exit the internalvolume while filling the thermal management container via the fillspout.

Containers described herein can be formed from any material notinconsistent with the objectives of the present disclosure. For example,in some embodiments, containers described herein comprise or are formedfrom a material which is operable to facilitate heat transfer between anexternal environment and the interior volume, or between the externalenvironment and a PCM disposed within the interior volume. For example,in some embodiments, the container's exterior surface can comprise or beformed from one or more materials that facilitate heat transfer, such asa thermal exchange material or a thermally conductive material. Anymaterial operable to permit thermal exchange from the container to theexternal environment can be used. Some non-limiting examples ofmaterials suitable for use in forming a container described hereininclude a polymeric or plastic material (such as a polyethylene, apolypropylene, polyethylene terephthalate, polyvinyl chloride,polycarbonate, polyoxymethylene, acrylonitrile butadiene styrene, or apolyether ether ketone), a metal or mixture or alloy of metals (such asaluminum), and a composite material (such as a composite fiber orfiberglass). It is to be understood that the material forming or used toform the container or the exterior surface of the container, in somepreferred embodiments, can generally form or define the entire body ofthe container or substantially the entire body of the container.

In some alternative embodiments, the container may be formed as anelongated structure such as a bar, tube, or other elongated prismstructure having an internal volume which may be filled or partiallyfilled with a PCM. In such implementations, the container has a firstend and a second end spaced apart from the first end, the separate endsdefining a length. The container in such embodiments also defines awidth. The container may have a large length to width ratio. Forexample, in some embodiments, the ratio of the length to the width is atleast 5:1, such as at least 10:1, at least 15:1, or at least 20:1.Additionally, a ratio of the length to the width may be even larger,such as at least 25:1, at least 30:1, or as large as at least 50:1, orat least 100:1. In some embodiments, the container has a length to widthratio between 5:1 and 100:1, between 5:1 and 50:1, between 5:1 and 25:1,between 5:1 and 20:1, between 5:1 and 15:1, or between 5:1 and 10:1. Insome cases, the length to width ratio may fall between 10:1 and 100:1,such as between 10:1 and 50:1, between 10:1 and 25:1, between 10:1 and20:1, or between 10:1 and 15:1. Other ratios are also possible, such asbetween 15:1 and 100:1, between 15:1 and 50:1, between 15:1 and 25:1, orbetween 15:1 and 20:1. Additionally, a ratio of the length to the widthmay be between 20:1 and 100:1, such as between 20:1 and 50:1, or 25:1and 50:1. Moreover, a ratio of the length to the width may be between25:1 and 100:1, such as between 50:1 and 100:1, or between 25:1 and50:1.

Thermal storage cells of the passive thermal storage battery orbatteries described herein have a second phase change material disposedwithin the interior volume of the container. A phase transitiontemperature of the second PCM may be selected based on the firstsetpoint associated with the active thermal storage battery, or may beselected to correspond to a second, different temperature or range oftemperatures. In instances where the second PCM's phase transitiontemperature differs from or otherwise does not correspond to the firstsetpoint temperature, the phase transition temperature may define orcorrespond to a second setpoint temperature. The second setpointtemperature can have any desired relationship with the operationalminimum and operational maximum temperatures not inconsistent with theobjectives of the present disclosure. For example, the second PCM (andcorrespondingly, the passive thermal storage battery) may be configuredto thermally manage the room or environment at or to a temperaturewithin the operational range, defined as being greater or higher thanthe operational minimum temperature, but lower than or less than theoperational maximum temperature. The phase transition temperature of thesecond PCM may be selected to function as desired with this secondsetpoint, although the phase transition temperature of the second PCMmay be the same or substantially the same as the second setpoint, thephase transition temperature may also differ from the setpoint. Suchconfigurations can be used to reduce normal HVAC function within therange to reduce energy consumption.

Alternatively, the second setpoint can be tied to different temperatureand/or performance parameters from the first setpoint. For example,while the first setpoint may be selected for an upper bound oroperational maximum temperature control, a second setpoint may beselected for a lower bound or operational minimum temperature control.Thus, the second setpoint may be equal to or lower than the operationalminimum temperature. Alternatively, the second setpoint may be higherthan the operational minimum temperature to reduce the likelihood of theoperational minimum temperature being reached, or to reduce thetemperature change as it approaches the operational minimum temperature.For example, the second setpoint (or, independent of the secondsetpoint, the phase transition temperature of the second PCM) may bewithin 2-5° C. greater or higher than the operational minimumtemperature, or may be within 2-5° C. less than the operational minimumtemperature. The second setpoint may alternatively be equal to or higherthan the operational maximum temperature, or within a few degrees aboveor below the operational maximum temperature. Therefore, the secondsetpoint (or, independent of the second setpoint, the phase transitiontemperature of the second PCM) may be within 2° C. and 5° C. greaterthan the operational maximum temperature, or within 2° C. and 5° C. lessthan the operational maximum temperature.

The phase transition temperature of the second PCM can be selectedindependently from and may be distinctly different from the phasetransition temperature of the first PCM. For example, in someembodiments, the phase transition temperature of the second PCM may beat least 10° C. higher than the phase transition temperature of thefirst PCM, such as between 10° C. and 40° C. higher, between 15° C. and30° C. higher, between 15° C. and 30° C. higher, or between 20° C. and30° C. higher than a phase transition temperature of the first PCM.

Any phase change material (“PCM”) or combination of PCMs notinconsistent with the objectives of the present disclosure may be usedin a component or method described herein, in particular as the firstPCM or second PCM of systems or methods described herein. The firstand/or second PCMs maybe selected individually or may be selected tohave coordinating or cooperating phase transition temperatures.Moreover, the PCM (or combination of PCMs) used in a particular instancecan be selected based on a relevant operational temperature range forthe specific end use or application. For example, in some cases, the PCMhas a phase transition temperature within a range suitable for coolingor helping to maintain a desired temperature or set point in aresidential or commercial building or portion thereof. As understood byone having ordinary skill in the art, a phase transition temperaturedescribed herein (such as a phase transition temperature of “X” ° C.,where X may be 23° C., for example) may be represented as a normaldistribution of temperatures centered on X° C. In addition, asunderstood by one having ordinary skill in the art, a PCM describedherein can exhibit thermal hysteresis, such that the PCM exhibits aphase change temperature difference between the “forward” phase changeand the “reverse” phase change (e.g., a solidification temperature thatis different from the melting temperature). In some such instances, thebuilding or portion thereof is a data center or data room, or an attic.In other embodiments, the building or portion thereof is a refrigeratedroom, warehouse, or other space, or is a freezer. In other instances,the PCM has a phase transition temperature suitable for the thermalenergy management of so-called waste heat. In some embodiments, the PCMhas a phase transition temperature within one of the ranges of Table 1below.

TABLE 1 Phase transition temperature ranges for PCMs (at a pressure of 1atm). Phase Transition Temperature Ranges 16-23° C. 16-18° C. 20-28° C.15-20° C. 8-15° C. 6-8° C. 0-6° C. −10° C. to 0° C.  −40° C. to −10° C.

Moreover, in certain embodiments, it may be desirable or even preferablethat a phase transition temperature of the PCM or mixture of PCMs is ator near a desired set-point temperature in an interior of a room or anexternal environment. Any desired room temperature or externaltemperature and associated phase transition temperature can be used. Forexample, in some embodiments, a phase transition temperature is betweenabout 15° C. and about 32° C. at 1 atm, such as between about 17° C. andabout 30° C. at 1 atm, between about 19° C. and about 28° C., or betweenabout 21° C. and about 26° C. at 1 atm. Further, in some cases, a phasetransition temperature is between about 17° C. and about 32° C. at 1atm, such as between about 19° C. and about 32° C. at 1 atm, betweenabout 21° C. and about 32° C. at 1 atm, between about 23° C. and about32° C. at 1 atm, or between about 25° C. and about 32° C. at 1 atm.Moreover, in some embodiments, a phase transition temperature is betweenabout 15° C. and about 30° C. at 1 atm, such as between about 15° C. andabout 28° C. at 1 atm, between about 15° C. and about 26° C. at 1 atm,or between about 15° C. and about 24° C. at 1 atm.

As described further herein, a particular range can be selected based onthe desired application. For example, PCMs having a phase transitiontemperature of 20-25° C. can be especially desirable to assist in thecooling of data centers, while PCMs having a phase transitiontemperature of 6-8° C. can be especially desirable for maintaining thetemperature of a refrigerated space. As another non-limiting example,PCMs having a phase transition between −40° C. and −10° C. can bepreferred for use in commercial freezer cooling.

Additionally, it may be desirable or even preferable that a phasetransition temperature of the PCM or mixture of PCMs is separate from adesired setpoint temperature of an interior of a room or an environment.Not intending to be bound by theory, such an arrangement could be placedin thermal communication with the room or environment when on-demandheating or cooling of the room or environment is desired by providing alarger difference between the ambient temperature of the room orenvironment and the phase transition temperature of the PCM. In suchembodiments, it may be desirable for the phase transition temperature tobe at least 5° C. greater or lesser than a temperature or setpointtemperature of the room or environment, such as between 5° and 35° C.greater or lesser, between 10° and 35° C. greater or lesser, between 15°and 35° C. greater or lesser, between 20° and 35° C. greater or lesser,between 5° and 30° C. greater or lesser, between 5° and 25° C. greateror lesser, between 5° and 20° C. greater or lesser, or between 5° and15° C. greater or lesser than the ambient temperature or the setpointtemperature of the room or environment. Such embodiments may be desiredwhere a fan or fan coil is used in tandem with the phase change materialto exhaust or otherwise disperse air that is warmer or cooler than thesetpoint temperature or ambient room temperature by an amount the sameor substantially the same as the phase transition temperature. Thus, insuch cases, the exhausted air may be at least 5° C., at least 10° C., atleast 15° C., or at least 20° C. warmer or cooler than the ambienttemperature of the air in the environment or room, such as such asbetween 5° and 35° C. greater or lesser, between 10° and 35° C. greateror lesser, between 15° and 35° C. greater or lesser, between 20° and 35°C. greater or lesser, between 5° and 30° C. greater or lesser, between5° and 25° C. greater or lesser, between 5° and 20° C. greater orlesser, or between 5° and 15° C. greater or lesser than the ambienttemperature or the setpoint temperature of the room or environment.

Further, a PCM of a device or method described herein can either absorbor release energy using any phase transition not inconsistent with theobjectives of the present disclosure. For example, the phase transitionof a PCM described herein, in some embodiments, comprises a transitionbetween a solid phase and a liquid phase of the PCM, or between a solidphase and a mesophase of the PCM. A mesophase, in some cases, is a gelphase. Thus, in some instances, a PCM undergoes a solid-to-geltransition. A solid to solid transition is also possible.

Moreover, in some cases, a PCM or mixture of PCMs has a phase transitionenthalpy of at least about 50 kJ/kg or at least about 100 kJ/kg. Inother embodiments, a PCM or mixture of PCMs has a phase transitionenthalpy of at least about 150 kJ/kg, at least about 200 kJ/kg, at leastabout 300 kJ/kg, or at least about 350 kJ/kg. In some instances, a PCMor mixture of PCMs has a phase transition enthalpy between about 50kJ/kg and about 350 kJ/kg, between about 100 kJ/kg and about 350 kJ/kg,between about 100 kJ/kg and about 220 kJ/kg, or between about 100 kJ/kgand about 250 kJ/kg.

In addition, a PCM of a device or method described herein can have anycomposition not inconsistent with the objectives of the presentdisclosure. In some embodiments, for instance, a PCM comprises aninorganic composition. In other cases, a PCM comprises an organiccomposition. In some instances, a PCM comprises a salt hydrate. Suitablesalt hydrates include, without limitation, CaCl₂).6H₂O, Ca(NO₃)₂.3H₂O,NaSO₄.10H₂O, Na(NO₃)₂.6H₂O, Zn(NO₃)₂.2H₂O, FeCl₃.2H₂O, Co(NO₃)₂.6H₂O,Ni(NO₃)₂.6H₂O, MnCl₂.4H₂O, CH3COONa.3H₂O, LiC₂H₃O₂.2H₂O, MgCl₂.4H₂O,NaOH.H₂O, Cd(NO₃)₂. 4H₂O, Cd(NO₃)₂.1H₂O, Fe(NO₃)₂.6H₂O,NaAl(SO₄)₂.12H₂O, FeSO₄.7H₂O, Na₃PO₄.12H₂O, Na₂B₄O₇.10H₂O, Na₃PO₄.12H₂O,LiCH₃COO.2H₂O, and/or mixtures thereof. The PCM may also be water. Inother embodiments, the PCM is not water.

In other embodiments, a PCM comprises a fatty acid. A fatty acid, insome embodiments, can have a C4 to C28 aliphatic hydrocarbon tail.Further, in some embodiments, the hydrocarbon tail is saturated.Alternatively, in other embodiments, the hydrocarbon tail isunsaturated. In some embodiments, the hydrocarbon tail can be branchedor linear. Non-limiting examples of fatty acids suitable for use in someembodiments described herein include caprylic acid, capric acid, lauricacid, myristic acid, palmitic acid, stearic acid, arachidic acid,behenic acid, lignoceric acid, and cerotic acid. In some embodiments, aPCM described herein comprises a combination, mixture, or plurality ofdiffering fatty acids. For reference purposes herein, it is to beunderstood that a chemical species described as a “Cn” species (e.g., a“C4” species or a “C28” species) is a species of the identified typethat includes exactly “n” carbon atoms. Thus, a C4 to C28 aliphatichydrocarbon tail refers to a hydrocarbon tail that includes between 4and 28 carbon atoms.

In some embodiments, a PCM comprises an alkyl ester of a fatty acid. Anyalkyl ester not inconsistent with the objectives of the presentdisclosure may be used. For instance, in some embodiments, an alkylester comprises a methyl ester, ethyl ester, isopropyl ester, butylester, or hexyl ester of a fatty acid described herein. In otherembodiments, an alkyl ester comprises a C2 to C6 ester alkyl backbone ora C6 to C12 ester alkyl backbone. In some embodiments, an alkyl estercomprises a C12 to C28 ester alkyl backbone. Further, in someembodiments, a PCM comprises a combination, mixture, or plurality ofdiffering alkyl esters of fatty acids. Non-limiting examples of alkylesters of fatty acids suitable for use in some embodiments describedherein include methyl laurate, methyl myristate, methyl palmitate,methyl stearate, methyl palmitoleate, methyl oleate, methyl linoleate,methyl docosahexanoate, methyl ecosapentanoate, ethyl laurate, ethylmyristate, ethyl palmitate, ethyl stearate, ethyl palmitoleate, ethyloleate, ethyl linoleate, ethyl docosahexanoate, ethyl ecosapentanoate,isopropyl laurate, isopropyl myristate, isopropyl palmitate, isopropylstearate, isopropyl palmitoleate, isopropyl oleate, isopropyl linoleate,isopropyl docosahexanoate, isopropyl ecosapentanoate, butyl laurate,butyl myristate, butyl palmitate, butyl stearate, butyl palmitoleate,butyl oleate, butyl linoleate, butyl docosahexanoate, butylecosapentanoate, hexyl laurate, hexyl myristate, hexyl palmitate, hexylstearate, hexyl palmitoleate, hexyl oleate, hexyl linoleate, hexyldocosahexanoate, and hexyl ecosapentanoate.

In some embodiments, a PCM comprises a fatty alcohol. Any fatty alcoholnot inconsistent with the objectives of the present disclosure may beused. For instance, a fatty alcohol, in some embodiments, can have a C4to C28 aliphatic hydrocarbon tail. Further, in some embodiments, thehydrocarbon tail is saturated. Alternatively, in other embodiments, thehydrocarbon tail is unsaturated. The hydrocarbon tail can also bebranched or linear. Non-limiting examples of fatty alcohols suitable foruse in some embodiments described herein include capryl alcohol,pelargonic alcohol, capric alcohol, undecyl alcohol, lauryl alcohol,tridecyl alcohol, myristyl alcohol, pentadecyl alcohol, cetyl alcohol,heptadecyl alcohol, stearyl alcohol, nonadecyl alcohol, arachidylalcohol, heneicosyl alcohol, behenyl alcohol, lignoceryl alcohol, cerylalcohol, and montanyl alcohol. In some embodiments, a PCM comprises acombination, mixture, or plurality of differing fatty alcohols.

In some embodiments, a PCM comprises a fatty carbonate ester, sulfonate,or phosphonate. Any fatty carbonate ester, sulfonate, or phosphonate notinconsistent with the objectives of the present disclosure may be used.In some embodiments, a PCM comprises a C4 to C28 alkyl carbonate ester,sulfonate, or phosphonate. In some embodiments, a PCM comprises a C4 toC28 alkenyl carbonate ester, sulfonate, or phosphonate. In someembodiments, a PCM comprises a combination, mixture, or plurality ofdiffering fatty carbonate esters, sulfonates, or phosphonates. Inaddition, a fatty carbonate ester described herein can have two alkyl oralkenyl groups described herein or only one alkyl or alkenyl groupdescribed herein.

Moreover, in some embodiments, a PCM comprises a paraffin. Any paraffinnot inconsistent with the objectives of the present disclosure may beused. In some embodiments, a PCM comprises n-dodecane, n-tridecane,n-tetradecane, n-pentadecane, n-hexadecane, n-heptadecane, n-octadecane,n-nonadecane, n-eicosane, n-heneicosane, n-docosane, n-tricosane,n-tetracosane, n-pentacosane, n-hexacosane, n-heptacosane, n-octacosane,n-nonacosane, n-triacontane, n-hentriacontane, n-dotriacontane,n-tritriacontane, and/or mixtures thereof.

In addition, in some embodiments, a PCM comprises a polymeric material.Any polymeric material not inconsistent with the objectives of thepresent disclosure may be used. Non-limiting examples of suitablepolymeric materials for use in some embodiments described herein includethermoplastic polymers (e.g., poly(vinyl ethyl ether), poly(vinyln-butyl ether) and polychloroprene), polyethylene glycols (e.g.,CARBOWAX® polyethylene glycol 400, CARBOWAX® polyethylene glycol 600,CARBOWAX® polyethylene glycol 1000, CARBOWAX® polyethylene glycol 1500,CARBOWAX® polyethylene glycol 4600, CARBOWAX® polyethylene glycol 8000,and CARBOWAX® polyethylene glycol 14,000), and polyolefins (e.g.,lightly crosslinked polyethylene and/or high density polyethylene).

Additional non-limiting examples of phase change materials suitable foruse in some embodiments described herein include BioPCM materialscommercially available from Phase Change Energy Solutions (Asheboro,N.C.), such as BioPCM-(−8), BioPCM-(−6), BioPCM-(−4), BioPCM-(−2),BioPCM-4, BioPCM-6, BioPCM 08, BioPCM-Q12, BioPCM-Q15, BioPCM-Q18,BioPCM-Q20, BioPCM-Q21, BioPCM-Q23, BioPCM-Q25, BioPCM-Q27, BioPCM-Q30,BioPCM-Q32, BioPCM-Q35, BioPCM-Q37, BioPCM-Q42, BioPCM-Q49, BioPCM-55,BioPCM-60, BioPCM-62, BioPCM-65, BioPCM-69, and others.

It is further to be understood that a device described herein cancomprise a plurality of differing PCMs, including differing PCMs ofdiffering types. Any mixture or combination of differing PCMs notinconsistent with the objectives of the present disclosure may be used.In some embodiments, for example, a thermal management plate or panelcomprises one or more fatty acids and one or more fatty alcohols.Further, as described above, a plurality of differing PCMs, in somecases, is selected based on a desired phase transition temperatureand/or latent heat of the mixture of PCMs.

Further, in some embodiments, one or more properties of a PCM describedherein can be modified by the inclusion of one or more additives. Suchan additive described herein can be mixed with a PCM and/or disposed ina device described herein. In some embodiments, an additive comprises athermal conductivity modulator. A thermal conductivity modulator, insome embodiments, increases the thermal conductivity of the PCM. In someembodiments, a thermal conductivity modulator comprises carbon,including graphitic carbon. In some embodiments, a thermal conductivitymodulator comprises carbon black and/or carbon nanoparticles. Carbonnanoparticles, in some embodiments, comprise carbon nanotubes and/orfullerenes. In some embodiments, a thermal conductivity modulatorcomprises a graphitic matrix structure. In other embodiments, a thermalconductivity modulator comprises an ionic liquid. In some embodiments, athermal conductivity modulator comprises a metal, including a pure metalor a combination, mixture, or alloy of metals. Any metal notinconsistent with the objectives of the present disclosure may be used.In some embodiments, a metal comprises a transition metal, such assilver or copper. In some embodiments, a metal comprises an element fromGroup 13 or Group 14 of the periodic table. In some embodiments, a metalcomprises aluminum. In some embodiments, a thermal conductivitymodulator comprises a metallic filler dispersed within a matrix formedby the PCM. In some embodiments, a thermal conductivity modulatorcomprises a metal matrix structure or cage-like structure, a metal tube,a metal plate, and/or metal shavings. Further, in some embodiments, athermal conductivity modulator comprises a metal oxide. Any metal oxidenot inconsistent with the objectives of the present disclosure may beused. In some embodiments, a metal oxide comprises a transition metaloxide. In some embodiments, a metal oxide comprises alumina.

In other embodiments, an additive comprises a nucleating agent. Anucleating agent, in some embodiments, can help avoid subcooling,particularly for PCMs comprising finely distributed phases, such asfatty alcohols, paraffinic alcohols, amines, and paraffins. Anynucleating agent not inconsistent with the objectives of the presentdisclosure may be used. In still other instances, an additive comprisesa fire retardant or fire-resistant material.

II. Methods of Storing and Releasing Thermal Energy

Referring now to FIGS. 4A-D. FIG. 4A illustrates a perspective view ofan additional example of an external view of an environmental enclosurewith a thermal energy storage and management system. FIG. 4B illustratesa perspective view of an additional example of a thermal energy storageand management system. FIG. 4C illustrates a perspective view of anadditional example of a thermal energy storage and management system.FIG. 4D illustrates the structure of an example embodiment of a passivethermal storage battery. In one aspect, methods of storing and releasingor otherwise managing thermal energy are described herein. In someimplementations, the method comprises disposing one or more of thesystems of Section I in thermal communication with a room orenvironment. In FIG. 4A the room is container, wherein the activethermal storage battery 412 resides as a module exterior to the mainroom, and wherein the passive thermal storage battery 410 is internal tothe room. The active thermal storage battery comprises 412 additionalcomponents such as a chiller 408, and a fan coil 406, that allows foroperation.

In one aspect, any method or configuration for placing the system inthermal communication with the room or environment may be used. In someembodiments, the active thermal storage battery may be disposed externalto the room or environment, but may be placed in thermal communicationwith the room or environment by one or more ducts, or may be in thermalcommunication at a fan coil or other air handling device. Further, insome implementations, the passive thermal storage battery may bedisposed internal to the room or environment, being in thermalcommunication by direct contact with ambient air in the room orenvironment.

Methods described herein may further comprise initiating the dischargingstate to maintain a temperature of the room by changing the first phasechange material from the first phase to the second phase. Initiating thedischarging state may be performed by the thermostat described inSection I, by a separate electrical switch which may or may not be inaddition to or in tandem with (and therefore instead of or in additionto) the thermostat. The electrical switch may be adapted to detect apower source or change in power source. The electrical switch is, insome implementations, adapted to detect a power outage and/or a returnof power. A discharging mode may be selected or initiated by thethermostat or electrical switch based on any individual condition orcombination of conditions as selected by the user.

Methods described herein may additionally comprise or include initiatinga charging state of the first phase change material to maintain thefirst phase change material in the first phase or to revert the phasechange material from the second phase to the first phase. Suchinitiation may be performed by any configuration or component describedabove in connection to the initiation of the discharging state, and maybe tied to alternative or opposite conditions of the charging state. Forexample, if a discharging state is initiated at or above the firstsetpoint temperature, the charging state may be initiated at a pointbelow the first setpoint temperature. Alternatively, if a dischargingstate is initiated when a power source is detected to change from thetraditional power grid to one or more batteries, the charging state maybe initiated when the power source is detected to change from the one ormore batteries to the traditional power grid. Moreover, in someembodiments, the charging state may be initiated with a complete ornear-complete phase transition from the first phase to the second phaseis detected in order to “recharge” or otherwise revert the first phasechange material to the first phase for further use in a dischargingstate at a later point.

Referring now to FIGS. 5A-B. FIG. 5A illustrates an example of a layoutor room for use with a thermal energy storage and management system andthe methods herein. FIG. 5B illustrates a top down view of a layout orroom for use with a thermal energy storage and management system and themethods herein. Methods described herein may, in some embodiments,further comprise changing the phase of the second phase change materialfrom a first phase to a second phase by exposing the second phase changematerial to an ambient temperature of the room above (or below) a phasechange temperature of the second phase change material. In FIG. 5A-B anexample of a room indicating dimensionality of passive thermal storagebatteries, for being placed on racks or stands. Further, the room isdisclosed depicting the transfer of ambient air to neighboringenvironmental structures or rooms. The second phase change material maybe subsequently reverted to the first phase by either exposing thesecond phase change material to an ambient temperature of the room on anopposing side of the first phase change (below the phase transitiontemperature if previously exposed to a temperature above the phasetransition temperature, or vice versa). The reversion to the first phasemay be aided by the use of a traditional HVAC system in thermalcommunication with the room, or may be the result of externalenvironmental temperature changes.

A heat source of the room, either which raises the temperature above thephase transition temperature of the second PCM, or to at/above the firstsetpoint or second setpoint (as appropriate) may comprise or include aplurality of batteries. The same battery or batteries may provide powerto the one or more optional powered components of the active thermalstorage battery.

III. Embodiments

Certain implementations of systems and methods consistent with thepresent disclosure are provided as follows:

Implementation 1. A thermal energy management system comprising: atleast one active thermal storage battery; and at least one passivethermal storage battery, wherein the at least one active thermal storagebattery comprises: a container; a heat exchanger disposed within thecontainer; and a first phase change material disposed within thecontainer and in thermal contact with the heat exchanger; and whereinthe at least one passive thermal storage battery comprises: a pluralityof thermal storage cells, individual thermal storage cells comprising: acontainer having an interior volume; and a second phase change materialdisposed within the interior volume of the container.

Implementation 2. The system of implementation 1, wherein: the activethermal storage battery has a charging state and a discharging state;while in the charging state, the active thermal storage batterymaintains the first phase change material in a first phase or returnsthe first phase change material to the first phase; and while in thedischarging state, the active thermal storage battery transfers thermalenergy from an environment external to the first phase change materialto the first phase change material by changing the first phase changematerial to a second phase from the first phase.

Implementation 3. The system of any of the preceding implementations,wherein the active thermal storage battery further comprises at leastone powered component.

Implementation 4. The system of implementation 3, wherein the at leastone powered component comprises a thermostat.

Implementation 5. The system of implementation 4, wherein: thethermostat initiates a shift from the charging state to the dischargingstate when a temperature of the environment external to the first phasechange material rises above a first setpoint temperature; theenvironment external to the first phase change material has anoperational minimum temperature and an operational maximum temperature;and the first setpoint temperature is greater than or equal to theoperational maximum temperature.

Implementation 6. The system of implementation 5, wherein the firstsetpoint temperature is higher than a phase transition temperature ofthe first phase change material from the first phase to the secondphase.

Implementation 7. The system of implementation 6, wherein the firstsetpoint temperature is between 5° C. and 50° C. higher than the phasetransition temperature of the first phase change material from the firstphase to the second phase.

Implementation 8. The system of implementation 7, wherein the firstsetpoint temperature is between 10° C. and 30° C. higher than the phasetransition temperature of the first phase change material from the firstphase to the second phase.

Implementation 9. The system of implementation 7, wherein the firstsetpoint temperature is between 20° C. and 40° C. higher than the phasetransition temperature of the first phase change material from the firstphase to the second phase.

Implementation 10. The system of implementation 5, wherein thethermostat initiates a shift from the discharging state to the chargingstate when a temperature of the environment external to the first phasechange material drops below the first setpoint temperature.

Implementation 11. The system of implementation 5, wherein: thethermostat initiates a shift from the discharging state to the chargingstate when a temperature of the environment external to the first phasechange material drops below a second setpoint temperature; and thesecond setpoint temperature is lower than the first setpointtemperature.

Implementation 12. The system of implementation 11, wherein the secondsetpoint temperature is less than the operational maximum temperature ofthe environment external to the first phase change material.

Implementation 13. The system of any of the previous implementations5-12, wherein the operational minimum temperature and operationalmaximum temperature are set according to performance ranges forelectronic equipment disposed in the environment external to the firstphase change material.

Implementation 14. The system of implementation 13, wherein theelectronic equipment comprises a plurality of batteries.

Implementation 15. The system of any of the implementations 4-14,wherein a phase transition temperature of the second phase changematerial is between the operational minimum temperature and theoperational maximum temperature.

Implementation 16. The system of any of the implementations 4-14,wherein a phase transition temperature of the second phase changematerial is less than or equal to the operational minimum temperature.

Implementation 17. The system of implementation 16, wherein the phasetransition temperature of the second phase change material is within 2°C. to 5° C. less than the operational minimum temperature.

Implementation 18. The system of any of the implementations 4-14,wherein a phase transition temperature of the second phase changematerial is greater than or equal to the operational maximumtemperature.

Implementation 19. The system of implementation 18, wherein the phasetransition temperature of the second phase change material is within 2°C. and 5° C. greater than the operational maximum temperature.

Implementation 20. The system of any of the implementations 3-19,wherein the at least one powered component comprises at least oneelectrical switch configured to initiate a shift from the charging stateto the discharging state and configured to initiate a shift from thedischarging state to the charging state.

Implementation 21. The system of implementation 20, wherein theelectrical switch is configured to detect a power outage and to initiatea shift from the charging state to the discharging state when the poweroutage is detected.

Implementation 22. The system of implementation 21, wherein theelectrical switch is configured to detect restoration of power after thepower outage and to initiate a shift from the discharging state to thecharging state with the restoration of power is detected.

Implementation 23. The system of any of implementation 3-23, wherein theat least one powered component comprises at least one chiller unit.

Implementation 24. The system of implementation 23, wherein: in thecharging state, the chiller unit is operable to maintain the first phasechange material in the first phase or to transition the first phasechange material from the second change to the first phase.

Implementation 25. The system of any of the implementations 3-24,wherein the at least one powered component comprises at least one fluidpump operable to flow fluid through the heat exchanger in the activethermal storage battery.

Implementation 26. The system of implementation 25, wherein the fluid iswater.

Implementation 27. The system of implementation 25, wherein the fluid isglycol.

Implementation 28. The system of any of the implementations 3-27,wherein the at least one powered component comprises at least one fancoil.

Implementation 29. The system of implementation 28, wherein the at leastone fan coil is operable to intake air from the environment external tothe first phase change material.

Implementation 30. The system of implementation 28 or 29, wherein the atleast one fan coil is operable to exhaust air from the active thermalstorage battery.

Implementation 31. The system of implementation 30, wherein theexhausted air has a temperature lower than a temperature of the ambientair in the environment external to the first phase change material.

Implementation 32. The system of implementation 31, wherein theexhausted air is at least 10° C. cooler than the temperature of theambient air in the environment external to the first phase changematerial.

Implementation 33. The system of implementation 31, wherein theexhausted air is at least 20° C. cooler than the temperature of theambient air in the environment external to the first phase changematerial.

Implementation 34. The system of any of implementation 3-33, wherein alatent heat of the first phase change material is higher than a powerdraw of the at least one powered component over a period of up to 5hours while in the discharging mode.

Implementation 35. The system of any of implementations 3-33, wherein alatent heat of the first phase change material is higher than a powerdraw of the at least one powered component over a period of up to 3hours while in the discharging mode.

Implementation 36. The system of any of the implementations 3-33,wherein the at least one powered component is powered by a traditionalenergy grid.

Implementation 37. The system of any of the implementations 3-34,wherein the at least one powered component is powered by at least onebattery.

Implementation 38. The system of any of the implementations 3-34,wherein the at least one powered component is powered by a traditionalenergy grid in the charging mode; and the at least one powered componentis powered by at least one battery in the discharging mode.

Implementation 38. The system of any of the preceding implementations,wherein the first phase change material has a phase transitiontemperature within one of the following ranges: 16-23° C.; 16-18° C.;15-20° C.; 6-8° C.; 0-6° C.; −10° C. to 0° C.; and −40° C. to −10° C.

Implementation 39. The system of implementation 38, wherein the firstphase change material has a phase transition temperature within one ofthe following ranges: 6-8° C.; 0-6° C.; −10° C. to 0° C.; and −40° C. to−10° C.

Implementation 40. The system of implementation 38, wherein the firstphase change material has a phase transition temperature within therange of 0−6° C.

Implementation 41. The system of any of the preceding implementations,wherein the second phase change material has a phase transitiontemperature within one of the following ranges: 16-23° C.; 16-18° C.;15-20° C.; 20-28° C.; 6-8° C.; and 8-15° C.

Implementation 42. The system of implementation 41, wherein the secondphase change material has a phase transition temperature within one ofthe following ranges: 16-23° C.; 20-28° C.

Implementation 43. The system of implementation 41, wherein the secondphase change material has a phase transition temperature within one ofthe following ranges: 6-8° C.; 0-6° C.; and −10° C. to 0° C.

Implementation 44. A method of managing the temperature of a room, themethod comprising: disposing one or more systems of any of the precedingclaims in thermal communication with the room, wherein the environmentexternal to the first phase change material is an interior of the room.

Implementation 45. The method of implementation 44 further comprising:initiating the discharging state to maintain a temperature of the roomor to reduce a temperature of the room by changing the first phasechange material from the first phase to the second phase.

Implementation 46. The method of implementation 45, wherein initiatingthe discharging state is performed by the thermostat when thetemperature of the room meets or exceeds the first setpoint temperature.

Implementation 47. The method of implementation 45, wherein the at leastone powered component is powered by the traditional power grid in thecharging state and by the at least one battery in the discharging state;and wherein initiating the discharging state is performed by theelectronic switch when a power source for the at least one poweredcomponent changes from the traditional power grid to the at least onebattery.

Implementation 48. The method of any of the implementations 44-47further comprising: changing the phase of the second phase changematerial from a first phase to a second phase by exposing the secondphase change material to an ambient temperature of the room above aphase change temperature of the second phase change material.

Implementation 49. The method of implementation 48 further comprisingreverting the second phase change material to the first phase by coolingthe room with an HVAC system of the room.

Implementation 50. The method of implementation 48 further comprisingreverting the second phase change material to the first phase byexposing the second phase change material to an ambient temperature ofthe room below the phase change temperature of the second phase changematerial.

Implementation 51. The method of any of the implementations 44-47further comprising: changing the phase of the second phase changematerial from a first phase to a second phase by exposing the secondphase change material to an ambient temperature of the room below aphase change temperature of the second phase change material.

Implementation 51. The method of implementation 51 further comprisingreverting the second phase change material to the first phase by heatingthe room with an HVAC system of the room.

Implementation 52. The method of implementation 51 further comprisingreverting the second phase change material to the first phase byexposing the second phase change material to an ambient temperature ofthe room below the phase change temperature of the second phase changematerial.

Implementation 53. The method of any of the implementations 44-53,wherein the room contains a plurality of batteries.

Implementation 54. The method of implementation 53, wherein a heatsource of the room comprises the plurality of batteries.

Implementation 55. The method of any of the implementations 44-54comprising initiating the charging state to maintain the first phasechange material in the first phase or to revert the phase changematerial from the second phase to the first phase.

Implementation 56. The method of implementation 55, wherein initiatingthe charging state is performed by the thermostat when the temperatureof the room drops to less than or equal to the first setpointtemperature.

Implementation 57. The method of implementation 55, wherein initiatingthe charging state is performed by the thermostat when the temperatureof the room drops to less than or equal to a second setpointtemperature, the second setpoint temperature being lower than the firstsetpoint temperature.

Implementation 58. The method of any of the implementations 55-57,wherein:

the at least one powered component is powered by the traditional powergrid in the charging state and by the at least one battery in thedischarging state; and initiating the charging state is performed by theelectronic switch when the power source of the at least one poweredcomponent changes from the at least one battery to the traditional powergrid.

Implementation 59. The method of implementation 44 wherein a pluralityof batteries are disposed in the room; and the room has an operationalminimum temperature and an operational maximum temperature, theoperational minimum temperature being defined by a temperatureassociated with a minimum operational capacity of the plurality ofbatteries and the operational maximum temperature being define by atemperature associated with a maximum operational capacity of theplurality of batteries.

Implementation 60. The method of implementation 59 further comprisinginitiating the discharging state when the temperature of the room meetsor exceeds the operational maximum temperature.

Implementation 61. The method of either of implementations 59 or 60further comprising initiating the charging state when temperature of theroom is less than the operational maximum temperature.

Various implementations of apparatus and methods have been described infulfillment of the various objectives of the present disclosure. Itshould be recognized that these implementations are merely illustrativeof the principles of the present disclosure. Numerous modifications andadaptations thereof will be readily apparent to those skilled in the artwithout departing from the spirit and scope of the present disclosure.For example, individual steps of methods described herein can be carriedout in any manner and/or in any order not inconsistent with theobjectives of the present disclosure, and various configurations oradaptations of apparatus described herein may be used.

1. A thermal energy management system, comprising: at least one activethermal storage battery; and at least one passive thermal storagebattery, wherein the at least one active thermal storage batterycomprises: a container; a heat exchanger disposed within the container;and a first phase change material disposed within the container and inthermal contact with the heat exchanger; and wherein the at least onepassive thermal storage battery comprises: a plurality of thermalstorage cells, individual thermal storage cells comprising: a containerhaving an interior volume; and a second phase change material disposedwithin the interior volume of the container.
 2. The system of claim 1,wherein the active thermal storage battery has a charging state and adischarging state; and while in the charging state, the active thermalstorage battery maintains the first phase change material in a firstphase or returns the first phase change material to the first phase; andwhile in the discharging state, the active thermal storage batterytransfers thermal energy from an environment external to the first phasechange material to the first phase change material by changing the firstphase change material to a second phase from the first phase.
 3. Thesystem of claim 1, wherein the active thermal storage battery furthercomprises at least one powered component.
 4. The system of claim 3,wherein the at least one powered component comprises a thermostat. 5.The system of claim 4, wherein the thermostat initiates a shift from thecharging state to the discharging state when a temperature of theenvironment external to the first phase change material rises above afirst setpoint temperature; and wherein the environment external to thefirst phase change material has an operational minimum temperature andan operational maximum temperature; and wherein the first setpointtemperature is greater than or equal to the operational maximumtemperature.
 6. The system of claim 5, wherein the first setpointtemperature is higher than a phase transition temperature of the firstphase change material from the first phase to the second phase.
 7. Thesystem of claim 5, wherein the thermostat initiates a shift from thedischarging state to the charging state when a temperature of theenvironment external to the first phase change material drops below thefirst setpoint temperature.
 8. The system of claim 5, wherein thethermostat initiates a shift from the discharging state to the chargingstate when a temperature of the environment external to the first phasechange material drops below a second setpoint temperature, and thesecond setpoint temperature is lower than the first setpointtemperature.
 9. The system of claim 5, wherein the first setpointtemperature is between 10° C. and 30° C. higher than the phasetransition temperature of the first phase change material from the firstphase to the second phase.
 10. The system of claim 3, wherein the atleast one powered component comprises at least one electrical switchconfigured to initiate a shift from the charging state to thedischarging state and configured to initiate a shift from thedischarging state to the charging state; and wherein the electricalswitch is configured to detect a power outage and to initiate a shiftfrom the charging state to the discharging state when the power outageis detected.
 11. The system of claim 8, wherein the second setpointtemperature is less than the operational maximum temperature of theenvironment external to the first phase change material.
 12. The systemof claim 3, wherein the at least one powered component comprises atleast one chiller unit; and wherein in the charging state, the chillerunit is operable to maintain the first phase change material in thefirst phase or to transition the first phase change material from thesecond change to the first phase; and wherein the at least one poweredcomponent comprises at least one fluid pump operable to flow fluidthrough the heat exchanger in the active thermal storage battery; andwherein the at least one powered component comprises at least one fancoil; and wherein the at least one fan coil is operable to intake airfrom the environment external to the first phase change material; andwherein the at least one fan coil is operable to exhaust air from theactive thermal storage battery; and wherein the exhausted air has atemperature lower than a temperature of the ambient air in theenvironment external to the first phase change material.
 13. The systemof claim 3, wherein the at least one powered component is powered by atraditional energy grid in the charging mode; and the at least onepowered component is powered by at least one battery in the dischargingmode.
 14. A method of managing the temperature of a room, the methodcomprising: disposing one or more thermal energy management systems ofclaim 1 in thermal communication with a room; and wherein theenvironment external to the first phase change material is an interiorof the room; and initiating a discharging state to maintain atemperature of the room or to reduce a temperature of the room bychanging the first phase change material from the first phase to thesecond phase.
 15. The method of claim 14, wherein initiating thedischarging state is performed by the thermostat when the temperature ofthe room meets or exceeds the first setpoint temperature.
 16. The methodof claim 14, wherein the at least one powered component is powered bythe traditional power grid in the charging state and by the at least onebattery in the discharging state; and wherein initiating the dischargingstate is performed by the electronic switch when a power source for theat least one powered component changes from the traditional power gridto the at least one battery.
 17. The method of claim 14, furthercomprising changing the phase of the second phase change material from afirst phase to a second phase by exposing the second phase changematerial to an ambient temperature of the room above a phase changetemperature of the second phase change material.
 18. The method of claim14, further comprising changing the phase of the second phase changematerial from a first phase to a second phase by exposing the secondphase change material to an ambient temperature of the room below aphase change temperature of the second phase change material.
 19. Themethod of claim 14, further comprising initiating the charging state tomaintain the first phase change material in the first phase or to revertthe phase change material from the second phase to the first phase. 20.The method of claim 14, further comprising a plurality of batteriesdisposed in the room; and the room has an operational minimumtemperature and an operational maximum temperature, the operationalminimum temperature being defined by a temperature associated with aminimum operational capacity of the plurality of batteries and theoperational maximum temperature being define by a temperature associatedwith a maximum operational capacity of the plurality of batteries.